Chevron ready to drill Orphan well

Chevron Canada expects to start drilling its second deepwater well in the Orphan Basin 430 kilometres northeast of St. John's by Sunday.

The company says it's taken extra precautions before sending the drill ship Stena Carron to the Lona-O55 wellsite located in water depths of 2.6 kilometres.

Chevron Canada expects to start drilling its second deepwater well in the Orphan Basin 430 kilometres northeast of St. John's by Sunday.

The company says it's taken extra precautions before sending the drill ship Stena Carron to the Lona-O55 wellsite located in water depths of 2.6 kilometres.

The precautions were prompted by the explosion of the Deepwater Horizon rig in the Gulf of Mexico that killed 11 people and the subsequent oil spill. Oil is gushing out of the ruptured well at a rate of more than 757,000 litres of crude a day since the rig sank April 22, two days after the explosion.

"In terms of this particular incident we do not know the cause," said Mark MacLeod, Atlantic Canada manager for Chevron.

"But we have redoubled our efforts with extra due diligence and focusing on, in particular, the blowout preventer."

He said Chevron hired a third-party consultant to review the maintenance and reliability of the Stena Carron's blowout preventer system.

"We've done a full inspection and testing of the blowout system, and all of the functions of that.

"Everything is good to go. We're very confident that we're ready to drill this well safely."

A blowout preventer is a wellhead valve designed to prevent potentially explosive surges of oil and gas during drilling. It effectively shuts down the well.

Built in 2008, the Stena Carron has all three ways to activate its blowout preventer: an acoustic signal sent to the seabed; sending an underwater robot to the seabed; and automatic hydraulic system to shut down a well.

"The well control system has a redundant process to automatically shut in the well if you lose both electrical power or hydraulics," said MacLeod.

One of BP's plans to stem the flow of oil from its ruptured well is drilling a relief well that will take several months to complete.

If this was necessary in the Orphan Basin, there is no deepwater rig currently in Newfoundland and Labrador waters.

The Henry Goodrich, which is currently in Marystown for maintenance, is rated for water depths of 1,500 metres. The GSF Grand Banks, which is drilling wells at North Amethyst, is rated for 450-metre waters.

MacLeod said Chevron would use deepwater drill ships on contract in the Gulf of Mexico.

"They could be mobilized to Newfoundland."

He said it would take about 11 days for a ship to steam to Newfoundland.

"They're equipped with enough riser, which is the pipe from the seabed to the drill ship itself, up to 3,000 metres of riser on those two vessels to be able to conduct a drilling operation in Newfoundland."

Sean Kelly, spokesman for the Canada-Newfoundland and Labrador Offshore Petroleum Board, said all exploration drill rigs in the province's offshore oil industry are equipped with blowout preventers.

He listed possible systems to activate the blowout preventer in an emergency: from the drill floor on the rig; using an underwater robot sent to the seabed to seal the wellhead; and an acoustic signal from the water surface to shut down the well.

A fail-safe shutdown is also an option.

"When the power is lost, it automatically closes," Kelly said.

"We require operators here to have at least one of those systems."

The GSF Grand Banks and the Henry Goodrich are equipped with underwater robots to activate the blowout preventer.

"But what they also have is a redundant system for shutting in well from the installation - so they have a main switch, which is in the drilling area, and they have a remote switch as well."

Kelly said the task of preventing blowouts takes place on the drill floor of the rig - well pressures and fluids are monitored during drilling.

"They're able to monitor the pressures that are coming up through the pipe.

"If they get a sense that there's an increase in pressure, they can adjust that by adding more drilling fluid, which is heavier and reduces the pressure."

It's not yet known why the blowout preventer on the Deepwater Horizon failed, but Kelly said offshore oil and gas regulators share information.

"As information comes to us from the appropriate authorities who are doing the investigation and follow-up, we will take that information and consider ... the implications for the Newfoundland offshore."

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David

July 02, 2010 - 13:22

After seeing Kelly interviewed on Here & Now, and now reading this, I have zero confidence that the CNLOPB has the first glimmer of technical knowledge of their job, or what pertinent questions to even ask the operators of these wells.

They are likely just glad ot have jobs that pay so well and to-dagte have required so little effort, let's just sit here enjoying the VIP access to the sidelines.

After seeing Kelly interviewed on Here & Now, and now reading this, I have zero confidence that the CNLOPB has the first glimmer of technical knowledge of their job, or what pertinent questions to even ask the operators of these wells.

They are likely just glad ot have jobs that pay so well and to-dagte have required so little effort, let's just sit here enjoying the VIP access to the sidelines.